Recoilless firearm



May 16, 1961 G. F. EDIN ETAL RECOILLESS FIREARM 2 Sheets-Sheet 1 Filed March 7, 1960 IN V EN TOR-5 m m D E N N W M E m N m WV W LA emw May 16, 1961 G. F. EDIN ETAL RECOILLESS FIREARM 2 Sheets-Sheet 2 Filed March 7, 1960 FIG. 4

FIG. 5

INVENTORS 0 v N A W M M 2m V TM 5 ma M NEH NM Wm A-rromvsrs RECOILLESS FIREARM Gunnar Filip Edin, Karlskoga, and Folke Gustav Tillander, Bofors, Sweden, assignors to Aktiebolaget Bofors, Bofors, Sweden, 2 Swedish corporation Filed Mar. 7, 1960, Ser. No. 13,339 Claims; or. sat-1.7

This invention relates to firearms and, more particularly, to a recoilless firearm.

Various types of recoilless firearms have been provided in which a gas exhaust funnel is attached to the rear part of the barrel by means of a hinge, such funnel being conveniently movable between a coaxial firing position with the barrel and an open position in which ammunition may be introduced into and removed from the firing chamber of the barrel. In this type of firearm, a dog clutch or other similar coupling may be used to lock the funnel in the coaxially aligned position with the barrel, and unlocked with respect thereto, in response to rotation of the funnel relative to the barrel. A striker bolt is also provided which moves radially of the barrel in a direction normal to the longitudinal axis of the barrel for firing the ammunition in the firing chamber.

It has been found that it is desirable to provide for the automatic cocking and locking of the firing mechanism of the firearm in response to the movements of the gas exhaust funnel relative to the barrel of the firearm. Accordingly an object of the present invention is to provide a firing mechanism for recoilless firearms of the type having a gas exhaust funnel hingedly supported upon a rear part of the barrel which will be cocked and locked solely by the relative movements between the gas funnel and the barrel, thus providing for the rapid and safe loading and firing of such weapons.

Another object of the present invention is to provide a recoilless firearm of the type described in which all of the parts of the firing mechanism are supported upon the barrel portion of the firearm so as to avoid the necessity of replacement thereof upon replacement of the gas exhaust funnel which is frequently replaced after repeated actual use of the firearm.

In carrying out the present invention, the striker bolt of the firing mechanism is connected to a spring loaded rod which is movable longitudinally along a rear part of the barrel. The rod is moved in its longitudinal direction by the turning movements of the gas exhaust funnel transmitted through a cam carried by the funnel. A blocking disc is supported upon the rear part of the barrel for movement between an engaged and disengaged position with the striker bolt at the beginning and end of such turning movement of the funnel upon the barrel, such blocking disc preventing movement of the striker bolt toward a firing position until the funnel is in the proper firing position.

All of the foregoing and still further object and advantages of this invention will become apparent from a study of the following specification, taken in connection with the accompanying drawing, wherein:

Figure 1 is a rear perspective view of the rear part of the barrel and gas exhaust funnel assembly of the firearm made in accordance with the present invention;

Figure 2 is a view similar to Figure 1, with parts broken away to show details of the firing mechanism;

Figure 3 is a bottom perspective view, with parts broken away, similar to Figure 2, showing still other parts of the present invention;

Figure 4 is a fragmentary longitudinal cross-sectional view of the operating parts of the present invention after the firing of a round of ammunition;

Figure 5 is a view similar to Figure 4, showing the manner in which the gas exhaust funnel is rotated toward an inoperative position allowing for the removal and insertion of the round of ammunition into the firing chamber of the barrel; and

Figure 6 is a fragmentary side elevational view of certain other operating parts of the present invention which provide for the setting of the firing mechanism in response to rotation of the funnel upon the rear part of the barrel.

Referring now more in detail to the drawing, a firearm made in accordance with the present invention is shown toinclude a barrel 1 having a firing chamber within which a round 2 of ammunition is disposed. A gas exhaust funnel 3 is pivotally supported by means of a hinge 6 upon the rear part 4 of the barrel 1. The front part 5 of the exhaust funnel 3 and the rear part 4 of the barrel have interlocking parts forming a dog type clutch which releasably secures the gas exhaust funnel 3 in a normally coaxially aligned locked position with the barrel 1. The hinge 6 includes an annular bearing ring 7 within which the gas exhaust funnel 3 is rotatably supported for accommodating rotation of the gas exhaust funnel relative to the barrel 12 to effect the release and locking engagement of the clutch parts. An injection arm 9 is also rotatably mounted upon the hinge pin 7a for ejecting the cartridge case of a fired round upon the opening of the gas exhaust funnel when an abutment 8 of the hinge member 7 strikes the outer end of the ejection arm 9, as shown in Figures 4 and 5.

A first cam means in the form of a cam plate 10 and an operating handle 11 is secured to the gas exhaust funnel 3. The cam plate 10 acts against one end of a firing pin 12 that is slidably supported within a tubular housing 12a of the barrel 1 for reciprocating longitudinal movement parallel to the longitudinal axis of the barrel. A compression coil spring 12b encircling a portion of the front end 12 yieldably urges the firing pin 12 into engagement with the cam plate 10. As is clearly shown in Figures 4 and 5 of the drawing, the rear portion of the firing pin 12 defines a pair of oblique surfaces 13 which serve as a second cam means for action with corresponding surfaces of a striker bolt 14 that is supported upon the rear part of the barrel for radial movement normal to the longitudinal axis" of the barrel to initiate the firing of the round 2.

The rear part 4 of the barrel 1 also supports a blocking disc 15 for limited arcuate movement. This blocking disc 15 is provided with two arcuate end grooves 16 and an intermediate central groove 17. Stop pins 15a carried by the rear part of the barrel are received within the end grooves 16 to limit a reciprocating arcuate movement of the blocking disc. the clutch part 5 of the funnel 3 is receivable within the central groove 17 of the blocking disc 15 in response to a closing movement of the funnel 3 into co-axial relationship with the barrel 1. Thus, upon rotation of the funnel 3, the driving pin 18 is operative to rotate the blocking disc 15 between the limits defined by the opposite ends of the arcuate grooves 16 and the stop pins 15a. The firing pin 12 is provided with a slot 19 within which a portion of the disc 15 is received upon rotation of the funnel to an unlocked position to prevent longitudinal movement of the firing pin 12 while the exhaust funnel 3 is not in locked coaxial relationship with the barrel 1. However, when the funnel 3 is rotated by the handle 11 to a locked position, the driving pin 8 carried by the A drive pin 18 carried upon- 3 clutch part of the funnel moves the part of the blockmg (1186 15 out of the slot 19 of the firing pin, thus releasing it for longitudinal movement by the action of the compression spring 12b when the trigger mechanism is rotated toward its coaxial position w'ith the barrel 1 upon the hinge 6, and the handle 11 rotated to the full line position shown in Figure 6, which effects the locking of the dog clutch parts of the funnel and barrel, also moving the cam plate out of blocking relationship with the rear end of the firing pin 12. Thus, when the firing pin 12 is displaced by its spring 1211, the oblique surfaces thereofact upon the striker bolt 14 to drive it radially inwardly into initiating engagement with the round 2 to elfect the firing of the round. The trigger mechanism for effecting the release of the firing pin 12 does not form a part of the present invention and is not shown in the drawing.

After the round has been fired, the parts assume the position shown in Figure 4. The funnel 3 is then rotated to unlock the clutch parts by rotating the handle 11, such rotation causing the cam plate 10 to move-the firing 1'2- forwardly against the action of the spring 12b, thus retracting the striker bolt 14 through the coaction of the cam surfaces 13 and the cooperating surfaces of the striker bolt 14. During the last stage of the turning of the funnel 3 within the bearing 7 of the hinge 6, the pin 18 moves the blocking disc arcuately into the recess 19 of the firing pin 12, thus preventing longitudinal movement of the firing pin 12. As a result, when the funnel 3 is rotated to the open position shown in Figure 5, the firing pin 12 is completely reset and secured in such reset position by the blocking disc 15 that is received within the recess or slot 19 of the terminal part of the firing pin 12. The opening of the funnel 3 also causes the ejector arm 9 to move the cartridge case of the fired round 2 outwardly to clear the chamber of the barrel for the next round.

When the new round is inserted into the chamber, the funnel 3 is then closed and secured to the barrel by the clutch parts. Until the parts are properly locked together, the firing pin 12 is locked in its retracted position by the disc 15, following which it is free to move forwardly upon operation of the trigger mechanism to effect the movement of the firing bolt 14 in the manner hereinbefore described.

It will now be recognized that relatively moving parts of the barrel and funnel automatically effect the resetting and safety locking of the firing pin and associated parts in response to movement of the funnel 3 toward the open position shown in Figure 5. As all of the operating parts of the firing mechanism are carried by the barrel, it becomes a simple matter to replace the funnel 3 Whenever required without interfering with or requiring replacement of any other parts of the firearm.

While the design of the invention illustrated in the drawing requires that the dog clutch parts 4, 5 rotate to an angle of 45, it will be recognized that such can be made of a screw clutch or other type of clutch requiring greater or lesser rotating movement in order to effect the desired setting of the firing parts and locking action between the funnel and the barrel.

While this invention has been described with particular reference to the construction shown in the drawing, it is to be understood that such is not to be construed as imparting limitations upon the invention, which is best defined by the claims appended hereto.

We claim: a

1. In a recoilless firearm of the type having a barrel an a hingedly supported gas exhaust funnel carried by the rear part of the barrel movable between an operative position forming a coaxial extension of said barrel and a load ing position extending normal thereto to permit a round of ammunition to be inserted into and removed from the chamber of the barrel, said funnel being rotatable coaxially of said barrel to effect the locking and releasing of said funnel in said operative position, a firing device including a striker bolt supported at the rear part of the barrel for movement normal to the longitudinal axis of the barrel, and a rod supported upon said barrel for reciprocating longitudinal movement, spring means yield-- ably urging said rod into one longitudinal direction, a

first cam means acting between said funnel and said rod' effecting movement of said rod against said spring meansin response to rotation of said funnel relative to said barrel in said normal position, and a second cam means acting between said rod and said bolt efi'ecting movement of said bolt radially of said barrel in response to movement of said rod.

2. In arecoilless firearm as set forth in claim 1 wherein said second cam means efiects radially inward movement of said bolt in response to movement of said rod by said spring means.

3. In a recoilless firearm as set forth in claim 2, wherein said first cam means comprises a cam plate carried by said funnel slidably acting against one outermost end of said rod to effect longitudinal movement of said rod against spring means in response to rotatlon of said funnel toward a released position with said barrel.

4. A firearm as set forth in claim 3, and further com prising a blocking plate slidably mounted for arcuate movement upon said rear part of said barrel, said rod having a slot slidably receiving said plate and blocking longitudinal movement of said rod by said spring means, and pin means carried by said funnel effecting movement of said plate into said slot of said rod to lock said rod in a retracted response to rotation of said funnel toward said released position of said barrel subsequently to longitudinal movement of said rod against said spring means by said first cam means.

5. A firearm as set forth in claim 4, and further comprising a drive pin secured to said funnel, said blockingplate defining an arcuate slot, and said drive pin being received within said slot in said normal operative position'of said funnel acting upon the ends of said slot in response to rotation of said funnel to effect said arcuate movement of said plate relative to said rod.

References Cited in the file of this patent UNITED STATES PATENTS 

